Not all golf balls lately are white; colored balls in a variety of colors have appeared on the market in response to golfers' preferences. In particular, stylish colored golf balls having an elegant feel are being developed to suit the tastes of women golfers.
Many colored balls with an elegant appearance currently sold on the market combine a fluorescent colored outermost layer with a polarizing pigment-containing paint. More casual, pastel-colored golf balls are also available on the market.
In order to create a sense of quality and elegance in a golf ball, it is generally common to include a fluorescent pigment or a fluorescent dye in the cover-forming material. However, such fluorescent pigments and dyes undergo major discoloration with exposure to ultraviolet light (weathering), leading to changes in the appearance of the ball in a short time and thereby making a sense of elegance difficult to maintain.
At the same time, there is a tendency for the ordinary consumer to desire such highly stylish colored golf balls to have the same high rebound and distance performance as conventional white golf balls. In general, to obtain a good distance performance, an ionic resin having an excellent rebound is used in an inner layer (intermediate layer). However, balls in which the intermediate layer is formed using an ionic resin tend to have a lower brightness and a more somber color. Hence, the ball has an increased rebound, but retaining a sense of quality and elegance has been difficult. Moreover, when a white pigment (titanium oxide) is added to a clear resin so as to keep the somber color of the intermediate layer from emerging on the surface of the ball, the opacity increases. Such an opacity also tends to detract from the sense of elegance in terms of the color appearance. The result is a pastel color tone, and imparting a sense of elegance to such a color is very difficult. Therefore, it has not been possible to achieve both a sufficient distance performance and stylishness in the same golf ball.
Accordingly, there exists a desire for the development of a golf ball which, even in cases where an intermediate layer made of an ionic resin is used in order to increase the ball rebound, is able to maintain a high brightness and also is endowed with a good rebound, weatherability and a sense of elegance.
Examples of the prior art relating to colored golf balls include JP-A 2000-254250, JP 3649568, JP-A 2007-144097 and JP-A 2009-45347 (and the corresponding U.S. Pat. application Ser. No. 2009-54176). However, none of these publications describe colored golf balls having a good rebound, a good durability and a sense of quality and elegance.